AUTHOR=Arrigo Alessandro , Aragona Emanuela , Bordato Alessandro , Amato Alessia , Saladino Andrea , Bandello Francesco , Parodi Maurizio Battaglia 

TITLE=High Reflectivity and Low Reflectivity Properties on OCTA Influence the Detection of Macular Neovascularization in AMD

JOURNAL=Frontiers in Physics

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2021.694035

DOI=10.3389/fphy.2021.694035

ISSN=2296-424X

ABSTRACT=<p><bold>Background:</bold> In this study, we aimed to discriminate high reflectivity and low reflectivity macular neovascularization (MNV) lesions secondary to age-related macular degeneration (AMD)and to assess the influence of blood flow features on the amount of MNV detected by optical coherence tomography angiography (OCTA).</p><p><bold>Methods:</bold> The study was designed as observational, cross-sectional. Type 1 and type 2 MNV lesions were included. All the patients underwent fluorescein angiography (FA), indocyanine green angiography (ICGA) and OCTA. MNV size was calculated on early FA for type 2 MNV and on both early and late phases of ICGA for type 1 lesions. From OCTA, we calculated both MNV size and MNV reflectivity. We assessed the agreement between FA/ICGA and OCTA MNV sizes. Moreover, we studied the relationship between MNV reflectivity properties and MNV OCTA detection.</p><p><bold>Results:</bold> Fifty eyes (50 patients) were included. MNV was identified as follows: 35 /70%) type 1 and 15 (30%) type 2. We found a good agreement between early ICGA size and OCTA size for type 1 MNV (2.10 ± 1.91 mm<sup>2</sup> vs 2.09 ± 1.87 mm<sup>2</sup>; <italic>p</italic> &gt; 0.05), whereas MNV lesions turned out to be remarkably bigger on late ICGA phase (3.41 ± 2.87 mm<sup>2</sup>; <italic>p</italic> &lt; 0.01). Interestingly, OCTA well-matched with FA in terms of MNV size for type 2 lesions (2.36 ± 2.15 mm<sup>2</sup> vs 2.37 ± 2.25 mm<sup>2</sup>). MNV reflectivity was higher in type 2 MNV and it was strongly associated with the OCTA ability to reconstruct the neovascular network.</p><p><bold>Conclusion:</bold> Our study quantitatively showed that MNV filling pattern and MNV blood flow reflectivity features influence the OCTA detection of the MNV in its entirety.</p>